Replacement resorption occurs as part of ankylosis.

Replacement resorption occurs as part of ankylosis.

• A. External resorption
• B. Internal resorption
• C. Replacement resorption
• D. Inflammatory resorption

Answer: (C)

Replacement resorption is the process by which the root structure is gradually resorbed and replaced by bone, occurring when the tooth becomes ankylosed due to loss or disruption of the periodontal ligament. With ankylosis, there is direct union between bone and the tooth surface, and osteoclasts resorb the root while osteoblasts lay down bone in its place. Over time this replaces the tooth with bone, which is exactly what “replacement resorption” describes. That connection to ankylosis is why this is the best answer. External resorption, internal resorption, and inflammatory resorption are different processes and do not inherently involve the tooth being replaced by bone as in ankylosis.

Replacement resorption is the process by which the root structure is gradually resorbed and replaced by bone, occurring when the tooth becomes ankylosed due to loss or disruption of the periodontal ligament. With ankylosis, there is direct union between bone and the tooth surface, and osteoclasts resorb the root while osteoblasts lay down bone in its place. Over time this replaces the tooth with bone, which is exactly what “replacement resorption” describes. That connection to ankylosis is why this is the best answer. External resorption, internal resorption, and inflammatory resorption are different processes and do not inherently involve the tooth being replaced by bone as in ankylosis.